Zhu Xuwei, Li Lihui, Tian Bo, Zhang Panpan, Wang Junjie
Institute of Highway Science, Ministry of Transport, Beijing 100088, China.
The Key Laboratory of Road and Traffic Engineering, Ministry of Education, Tongji University, Shanghai 201804, China.
Materials (Basel). 2023 Jan 11;16(2):719. doi: 10.3390/ma16020719.
The high value use of agricultural and livestock waste resources in the context of a low carbon economy is a challenge that currently plagues many countries. Yak dung, as a waste resource from livestock farming in the plateau, is considered to be a misplaced treasure. In this work, yak dung was processed into yak dung fiber (YDF) and yak dung ash (YDA), respectively, and the microscopic morphology of the YDF and YDA was assessed using scanning electron microscopy (SEM). The elements in the YDA were analyzed by energy dispersive X-ray spectroscopy (EDX). Moreover, cementitious composites were prepared with YDF at 0%, 0.3%, 0.5% and 0.7% and by replacing cement with YDA at 5%, 10% and 15% to assess the workability, mechanical properties and shrinkage properties of cementitious composites containing different YDF types (alkali treated and untreated), contents and different YDA contents. The results showed that alkali-treated YDF and YDA contain a large number of honeycomb structure pores, and the strength of cementitious materials with alkali-treated YDF was higher. The addition of YDF had a negative effect on the fluidity and compressive strength of the cementitious material, but the 0.3% YDF was beneficial in increasing its flexural strength. The compressive strength and flexural strength first increased and then decreased with the increase of YDA content. Both YDF and YDA inhibited the shrinkage of the cement paste, and the shrinkage strain of the cement matrix composites containing 0.3% YDF and 10% YDA was reduced by 51.1% compared to the control group. This work is expected to promote the application of yak dung waste in cementitious materials.
在低碳经济背景下，农牧业废弃物资源的高值化利用是当前困扰许多国家的一项挑战。牦牛粪便作为高原地区畜牧养殖的一种废弃物资源，被认为是一种被错置的宝藏。在本研究中，分别将牦牛粪便加工成牦牛粪纤维（YDF）和牦牛粪灰（YDA），并采用扫描电子显微镜（SEM）对YDF和YDA的微观形态进行了评估。通过能量色散X射线光谱仪（EDX）分析了YDA中的元素。此外，制备了YDF含量分别为0%、0.3%、0.5%和0.7%，以及YDA替代水泥量分别为5%、10%和15%的水泥基复合材料，以评估含有不同类型（碱处理和未处理）、不同含量YDF以及不同YDA含量的水泥基复合材料的工作性能、力学性能和收缩性能。结果表明，碱处理后的YDF和YDA含有大量蜂窝状结构孔隙，且含碱处理YDF的水泥基材料强度更高。YDF的加入对水泥基材料的流动性和抗压强度有负面影响，但0.3%的YDF有利于提高其抗折强度。抗压强度和抗折强度随YDA含量的增加先增大后减小。YDF和YDA均抑制了水泥浆体的收缩，与对照组相比，含0.3%YDF和1
